Field of Invention
The present invention relates to medical devices. More particularly, the invention relates to an implant which in one embodiment facilitates sutured side-to-side arteriovenous fistula (AVF) creation and maintains the patency thereof.
Background
End-stage renal disease (ESRD) is a growing problem in the United States and abroad, with the number of patients requiring treatment far outstripping the number of donor kidneys available. Those patients who are unable to receive a kidney transplant are treated by dialysis, with roughly ten times as many patients receiving hemodialysis as all other forms combined.
To minimize treatment time, hemodialysis requires a large blood volume flow rate. Increasing flow is typically achieved through the surgical creation of an arteriovenous shunt. This creates a low resistance pathway, significantly increasing flow through a graft or an arteriovenous fistula.
In practice, AVF is preferred to graft usage because fistulas have better long-term patency rates and reduced incidences of secondary interventions after creation. However, the surgical creation of an AVF and the subsequent venous tissue remodeling required to realize optimized flow rates is only successful in approximately half of surgical procedures. Failures involving AVF are largely due to stenosis via neointimal hyperplasia and thrombosis. A potential cause of neointimal hyperplasia is the exposure of venous tissue to the abnormal hemodynamic conditions resulting from significantly increased flow rates and pulsatility of the added arterial blood flow. In other cases, large flow rates can cause extreme dilation and result in oversized fistulas which fail to achieve the purpose for which they were created.
There exists a need for an improved method of creating arteriovenous fistula and maintaining the patency thereof, including implantation of devices designed to achieve these purposes.